Insecticidal compositions containing carbamates of 5- and 6-membered hetero-sulfur compounds and method of controlling insects with same



United States Patent This application is a divisional ofco-pendingapplication for Letters Patent, Ser. No. 225,135, filed on Sept. 20,1962, now US. Patent 3,193,561.

The present invention relates to carbamates of heterocyclic sulfurmoieties containing from five to six atoms and has for its principalobject the utilization of such carbamates as the active component of aninsecticidal composition.

The novel hetero-sulfur compounds prepared in accordance with thepresent invention may be represented by the general formula:

wherein R R R R R and R are hydrogen, lower alkyl or phenyl radicals,which may be the same or different, n is an integer from 0 to 1, Qrepresents either a sulfur or oxygen atom, and R and R are hydrogen orlower alkyl radicals.

In general, the compounds of the present invention may be prepared by anumber of diverse processes. Illustrative of one such process involvesthe reaction between (1) either a 2-oximino derivative of theheterocyclic sulfur moiety or the corresponding alkali metal saltthereof and (2) either an isocyanate or a carbamyl halide. Each reactantis advantageously present in equimolar amounts at temperatures rangingfrom about 0 C. to about 100 C.

The over-all reaction may be represented as:

and

wherein R R R R R R and n represent the 'same values as above; R and Rrepresent hydrogen or lower alkyl and may be the same or different; M isan alkali metal, such as sodium, potassium or lithium; and X is ahalogen atom, such as fiuoro, chloro, bromo or iodo.

Alternatively, the carbamates of the present invention can be preparedby the reaction between 2-oximino heterocyclic sulfur compounds or thecorresponding alkali metal salts thereof and phosgene, followed byfurther reaction with either ammonia, a primary amine or a secondaryamine in accordance with the following over-all reactions:

and

wherein R1, R2, R3, R4, R5, R6, R7, R3, Q and n all represent the samevalues as above.

It is an advantage of the present invention that a large number of alkylisocyanates and carbamyl halides may be employed in herein-above definedReactions [I] or [Ia]. Such illustrative but non-limitative reactantsinclude, for instance, methyl isocyanate, ethyl isocyanate, propylisocyanate, t-butyl isocyanate, n-pentyl isocyanate, n-hexyl isocyanateand heptyl isocyanate as well as carbamyl chloride, N-methyl carbamylchloride, N,N-dimethyl carbamyl chloride, N,N-diethyl carbamyl bromide,N,N- dipropyl carbamyl chloride and N,N-dibutyl carbamyl iodide.

In the above reaction designated as [B], ammonia and a variety of alkylamines can advantageously be employed. Exemplary amines are:methylamine, ethylamine, propyl amine, butylamine, dimethylamine,diethylamine, dipropylamine, dibutylamine, diamylamine, dihexylamine,homologs and isomers thereof.

The heterocyclic reactants possessing the desired 2- oximino substituentcan be prepared from a variety of heterocyclic compounds which include:

2-imino-1,3-dithiolane, 2-imino-1,3 -oxathiolane, 2-i-mino-1,3-dithiane,2-imino-1,3-oxathiane, 2-methylimino-1,3 -dithiolane,2-ethylimino-1,3-oxathiolane, 2-n-propylimino-1,3 -dithiane,Z-n-butylamino-1,3-oxathiane,

as well as the ring-substituted lower alkyl or ring-substituted phenylderivatives thereof.

In general, the Z-imino heterocyclic sulfur reactant can be initiallyprepared in a straightforward manner by bringing into reactivecombination approximately equimolar amounts of a cyanogen halide and athiol, such as ethanedithiol-1,2, 1-hydroxy-2 mercapto-ethane,propanedithiol- 1,2, propanedithiol-l,3,1-mercapto-3-hydroxy propane, 1,3-dithiol-2-methyl-n-propane, butanedithiol-l,2 or2,5-dimethylhexanedithiol-3,4, homologs and isomers thereof, preferablyin the presence of an acidified alcoholic catalyst, such as hydrogenchloride-ethanol when utilizing a dithiol as the reactant. However, a2-alkylimino heterosulfur reactant can be prepared by reacting a loweralkyl ammonium alkyldithiocarbamate salt and an alkylene dihalide, suchas ethylene bromide, ethylene chloride, 1,2- dibromopropane,1,3-diiodopropane and 1,3-dichloropropane. Resultant 2-iminoheterocyclic sulfur hydrohalide or 2-alkylimino-heterocyclic sulfurhydrohalide can be reacted next with a hydroxylamine salt, such aseither hydroxylamine hydrohalide or hydroxylamine sulfate, to obtainZ-oximino-hetero-sulfur derivatives which are utilized as reactantsherein.

In order to facilitate a further understanding of the present invention,the following illustrative examples are presented. These are not to betaken as limitative of the invention. Unless otherwise stated, the partsare by weight.

EXAMPLE 1 Preparation of 2-imino-1,3-dithiolane hydrochloride To amixture of 25.0 parts of ethanedithiol in 125 parts (by volume) of dryacetonitrile at C.-5 C. in a vessel equipped with a condenser, are added17.2 parts of cyanogen chloride over a thirty minute period. Afterstirring at 35 C.40 C. for four hours, the mixture remains at roomtemperature overnight. The product is collected as colorless needlesweighing 27.3 parts, corresponding to a yield of 66.2 percent of theory,and melting at 218 C.220 C. with decomposition.

Analysis for C H NClS Calculated: CI, 22.8%. Found: Cl, 22.6%.

In the foregoing, similar results are obtained where cyanogen bromide issubstituted for cyanogen chloride.

4 EXAMPLE 2 Preparation of 2-z'mino-1,3-oxalhiolane hydrochloride Amixture of 50 parts of mercaptoethanol in 200 parts of benzene in aflask equipped with a stirrer, ice-watercooled condenser, gas inlet tubeand thermometer is heated to 50 C. and 44 parts of a gaseous cyanogenchloride are passed in over a two and one-half hour period. Thetemperature rises spontaneously to 60 C.-65 C. when about half of thecyanogen chloride is added, solids begin form ing, and the temperaturestays at this level during the remainder of the addition period. Afterthe mixture has been maintained at 40 C.45 C. for an additional four andone-half hours and stayed overnight at room temperature, the solid2-imino-1,3-oxathiolane hydrochloride amounting to 47 parts, or 52percent of theory, is collected.

EXAMPLE 3 Preparation 0 2-z'min0-5-methyl-1,3-ovcathiolane hydrochlorideExample 1 above is repeated in every detail, except that1-hydroxy-2-mercapto-n-propane is substituted for the ethanedithiolreactant therein. Resultant product, 2-imino- S-methyl-1,3-oxathiolane,is obtained in good yield and purity.

EXAMPLE 4 Preparation of Z-isopropylimino-I,3-dithiolane To a stirredmixture of 10.0 parts of ethylene bromide and 8.8 parts of potassiumcarbonate in 75 parts of absolute ethanol at 38 C.40 C. are added 10.4parts of isopropylamino ammonium isopropyldithiocarbamate in smallincrements over a one-hour period. After heating to reflux for tenminutes, the mixture is cooled, resultant solids are filtered off, andthe alcohol solution diluted with about three volumes of water.Extraction of the aqueous mixture with ether followed by stripping oh?the ether and distillation of the residue affords 6.5 parts or 76percent of theory of 2-isopropylimino-1,3-dithiolane having a boilingpoint of 81 C.-83 C./0.30 mm. Hg and a refractive index (n of 1.5671.

Analysis for C H NS Calculated: C, 44.68; H, 6.88; S, 39.76. Found: C,44.82; H, 7.09; S, 39.85.

EXAMPLE 5 Preparation of 4-methyl-Z-methylimino-I,3-dithiolane To astirred mixture of 99.7 parts of 1,2-dibromopro panein 300 parts ofethanol at 40 C. are added 65.9 parts of methylamino ammoniummethyldithiocarbamate over a period of one hour. After heating for anadditional hour at 50 C., the mixture is cooled, 300 parts of ether andone equivalent of sodium hydroxide are added, and the organic phase isseparated. The organic phase is dried with magnesium sulfate and thesolvent stripped. Distillation of the residue yields 15.9 parts ofdesired product and 22.8 parts of unreacted dibromopropane. A sample ofthe product on redistillation boils at 54 C./ 0.04 mm., and has arefractive index (n of 1.5781.

Analysis for C H NS Calculated: C, 40.78; H, 6.16; S, 43.55. Found: C,40.94; H, 6.17; S, 43.52.

EXAMPLE 6 Preparation of 2-imino-L3-dithiane hydrochloride To a mixtureof 130 parts of chloroform nearly saturated with dry hydrogen chloridein a flask equipped with a stirrer, ice-water-cooled condenser, gasinlet tube and thermometer are added 27.7 parts of propane-1,3-dithiol.Subsequent slow addition of 18 parts of gaseous cyanogen chloride over atwo-hour period causes a spontaneous temperature rise to 42 C. Aftercompletion of cyanogen chloride addition, the mixture is heated at 50C.55C. for one hour. The crystalline product amounts to 24.1 parts or55.5% of theory. The sample is sublimed at EXAMPLE 7 Preparation of2-oximino-L3-dithiolane A mixture of 0.21 part of2-isopropylimino-1,3-dithiolane obtained in Example 4 above, and 0.10part of hydroxylamine hydrochloride is heated on the steam bath with 3.0parts of water and sufiicient ethanol to initially dissolve thereactants. After two hours, most of the ethanol has boiled away and, onice-cooling the remaining mixture, the product crystallizes. The wateris decanted off and the solids are rinsed with water and vacuum-dried.The 2-0ximino-l,3-dithiolane, melting point 124 C.-127 C., weighs 0.14part or 80 percent of theory.

EXAMPLE 8 Preparation of Z-oximino-I,3-oxathilane A mixture consistingof 55.0 parts of 2-imino-1,3-dithiolane hydrochloride obtained inExample 1 above, 27.1 parts of hydroxylamine hydrochloride and 34.8parts of sodium acetate is mixed at 70 C.75 C. for one hour.Crystallization of the resultant oxime occurred. After cooling to roomtemperature and filtering, a 87.6 percent yield of colorless2-oximino-1,3-dithiolane is obtained, melting at 126 C.-128 C.

EMMPLE 9 Preparation of 2-oximino-1,3-0xathiolane To a stirred mixtureof 19.0 parts of 2-imino-1,3-oxathiolane hydrochloride and 10.4 parts ofhydroxylamine hydrochloride in 75 parts of water are added 12.3 parts ofsolid sodium acetate in increments over a two-hour period. Aftertwenty-four hours, 12.5 parts of solid sodium bicarbonate are addedslowly. The mixture is filtered, the filtrate is diluted with an equalvolume of a saturated salt solution, and the mixture is continuouslyether extracted for fourteen hours. The semi-solid residue obtained byevaporation of the ether is extracted several times with hot benzene.The benzene on dilution with hexane gives several fractions of solidswhich are combined. Recrystallization from benzene plus a small quantityof hexane affords 5.2 parts, or 32 percent of theory of2-oximino-1,3-oxathiolane having a melting point of 111 C.-116 C. Samplerecrystallized further melts at 116.4 C.117.2 C.

Analysis for C H NO S. Calculated: C, 30.24; H, 4.23; N, 11.76; S,26.91. Found: C, 30.29; H, 4.24; N, 11.76;

EXAMPLE Preparation of 4-methyl-2-oximino-1,3-dithiolane A solution of10.0 parts of 4-methyl-2-methylimino- 1,3-dithiolane and 5.2 parts ofhydroxylamine hydrochloride in 80 parts of 40% ethanol is heated on asteam bath for four hours. The yellow oily product obtained afterextracting the reaction mixture with ether, treating the ether solutionwith activated carbon and magnesium sulfate, and stripping off theether, amounts to 9.1 parts or 90 percent of theory. The infraredspectrum shows the expected C=N-- band absorption at 1600 emf.

EXAMPLE 11 Preparation of 2-oximino-1,3-dithiane A mixture of 18.0 partsof 2-imino-l,3-dithiane hydrochloride, 8.1 parts of hydroxylaminehydrochloride, and 9.6 parts of sodium acetate in 200 parts of water isslowly heated to 64 C. over a one-hour period and then to 75 C. over thenext fifteen minutes. After cooling the mixture, extraction with etherin the usual manner affords 11.6 parts of product as an oil which sooncrystallizes. Recrystallization from the benzenehexane mixture gives 8.9parts of the oxime, melting point 92.4 C.9'4.8 C. A small samplerecrystallized once again for analysis melts at 940 C.-95.0 C.

Analysis for C4H7NOS2. Calculated: C, 32.19; H, 4.73. N, 9.39; S, 42.97.Found: C, 32.11; H, 4.86; N, 9.30; S, 42.98.

EXAMPLE 12 Preparation of Z-oxz'mirzo-S-methyl-I,3-oxathiolane To anagitated mixture of 100.0 parts of 2-imino-5- methyl 1,3-oxathiolanehydrochloride and 45.3 parts of hydroxylamine hydrochloride in 200 partsof dry methanol are added in increments at room temperature over a. onehour period 53.4 parts of sodium acetate. After stirring the mixture atroom temperature overnight, it is heated at 50 C. for two hours and thencooled. There are then added 66 parts of potassium bicarbonate and 200parts of ether followed by stirring for two hours, and the reactionmixture is then filtered. The filtrate is concentrated. Extraction ofthe residue successively with benzene and ether, followed byconcentration of the ether-benzene mixture, yields 56.9 parts of crudeproduct. The oil remaining from the benzene-ether extraction is mixedwith methanol and 200 parts of chloroform and the mixture is washedsuccessively with partially saturated salt solution and with a saturatedsalt solution. After filtering through magnesium sulfate, concentrationof the chloroform mixture leaves another 23.0 parts of crude oxime.Recrystallization of the combined crude oxime from a 1:1 benzeneethermixture gives 40.0 parts, or 46.2 percent of theory of product, having amelting point equal to 92 C.94 C. A sample, vacuum sublimed foranalysis, melts at 94.0 C.-95.2 C.

Analysis for C H NO S. Calculated: C, 36.07; H, 5.30; N, 10.52; S,24.08. Found: C, 36.27; H, 5.45; N, 10.56; S, 24.21.

EXAMPLE 13 Preparation of 4,5,-dimethyl-2-oximino-l,3-dithiolane Amixture of 15.0 parts of 4.5-dimethyl 2 imino 1, 3-dithiolanehydrochloride, 6.3 parts of hydroxylamine hydrochloride, and 7.8 partsof sodium acetate in 115 parts of water are stirred and heated at 75 C.C. for one hour. The solids, which form on ice-cooling the mixture, arecollected, washed with water and allowed to dry. Recrystallization frombenzene-hexane affords 10.1 parts, or 75.6 percent of theory, ofcolorless product melting at C.103 C.

Analysis for C H NOS Calculated: C, 36.78; H, 4.38; N, 8.58; S, 39.27.Found: C, 37.33; H, 4.43; N, 8.57; S, 39.37.

EXAMPLE 14 Preparation of 4-n-bazyl-Z-oximino-I,3-dithi0lane A mixtureof 13.0 parts of 4-nbutyl-2-imino-1,3-dithiolane hydrochloride, 4.7parts of hydroxylamine hydrochloride, and 5.8 parts of sodium acetate isstirred and heated at 70 C.80 C. for two hours. On cooling, a viscousoil separates. The water is decanted away from the oil and the oil takenup with ether and dried by filtration through magnesium sulfate.Evaporation of the ether gives 10.7 parts, or 91.8% of theory, of theoxime. The infrared absorption curve of the oxime shows bands at 950cm.- and 1580 cm.- attributable to the =NO and =C=N- bonds,respectively, and several bands in the 2800 cm. and 3300 cm." regionassignable to the OH function.

EXAMPLE 15 Preparation of 4-phenyl-Z-oximinm],3-dithiolane The procedureof Example 14 is repeated in every detail, except that 2.8 parts of4-phenyl-2-imino-1,3-dithiolane hydrochloride are employed in lieu ofthe 4-n-butyl dithiolane reactant to provide 2.3 parts, or 91.7 percentof theory, of 4-phenyl-2-oximino-l,3-dithiolane as a viscous oil. Theinfrared absorption curve of this product, in addition to showingnumerous bands assignable to the phenyl rings, shows a =C=N band at 1575cm.- and three bands assignable to the NOH function at 2800 cmf 2920 cm.and 3200 (broad) cmf EXAMPLE 16 Preparation of N-methyl carbamate of2-0ximino-1,3-

dithiolane To 5.3 parts of 2-oximino-1,3-dithiolane dissolved partiallyin 20 parts of dry ether in a suitable ice-cooled reaction flask areadded 2.5 parts (by volume) of methyl isocyanate and 0.1 part oftriethylamine. The flask is then removed from the ice-bath and themixture is stirred at room temperature for twelve hours. A yield of 97percent of desired carbarnate is obtained as a solid melting at 81 C.-83C. Recrystallization from the benzene-hexane mixture yields N-methylcarbamate of 2-oximino-1,3-dithiolane melting at 822 C.83.4 C.Calculated for the carbon, hydrogen and sulfur contents are,respectively, 31.2; 4.2 and 33.4, all in percent. It is found that thecarbon, hydrogen and sulfur analysis, respectively, is: 31.4; 4.4 and33.3, all in percent.

Substituting n-hexyl isocyanate (6.08 parts) for the methyl isocyanateabove, N-hexyl carba-mate of 2-oximino- 1,3-dithiolane is obtained in 93yield.

EXAMPLE 17 Preparation of N-ethyl-carbamate of 2-0ximin0-1,3-

dithiolane To a suitable ice-cooled reaction vessel are added 5.0 partsof 2-oximino-1,3-dithiolane in 20 parts (by volume) of dry ether and 2.6parts (by volume) of ethylisocyanate and 0.1 part of triethylamine. Thecontents of the flask are then stirred for twenty-four hours at roomtemperature. After stripping off the ether, the ethyl carbamate productis collected as an oil which crystallizes on seeding. Recrystallizationfrom benzene-petroleum ether yields 55 percent of the N-ethyl carbamateproduct having a melting point of 510 C.52.5 C. and analyzes in percentas follows for C H N O S Calculated: C, 34.9; H, 4.9; S, 31.1. Found: C,35.1; H, 4.8; S, 31.2.

EXAMPLE 18 Preparation of N,N-dimethyl-carbamate of 2-oximin0-1,3-dithilane To a suitable reaction vessel are added 7.0 parts of thesodium salt of 2-oximino-1,3-dithiolane in 50 parts (by volume) of dryacetone and 4.7 parts of dimethyl carbamyl chloride. After refluxing themixture for three hours, an equal volume of water is added and thedimethyl carbamate product is extracted with a 50-50 ether-benzenemixture. Recrystallization from a methanol-Water mixture yields 8percent of the desired product having a melting point of 94.2 C.95.0 C.and analyzes in percent as follows for C H N O S Calculated: C, 34.9; H,4.9; S, 31.1. Found: C, 35.2; H, 4.9; S, 31.2.

EXAMPLE 19 Preparation of the carbamate of Z-oximino-I,3-dithi0lane Intoan ice-cooled reaction vessel equipped with an icecooled condenser andcontaining 75 parts (by volume) of dry ether are added 18.9 parts ofphosgene. To this mixture is next introduced in increments a total of10.0 parts of the sodium salt 'of 2-oximino-1,3-dithiolane over athirty-minute period. After stirring the mixture at room temperature forabout fifteen hours, excess phosgene is removed by distillation. Theremaining mixture is icecooled. The latter is then added to a solutionof 2.2 parts of ammonia in 100 parts (by volume) of dry acetonitrile.After removing the ice bath to allow the mixture to come to roomtemperature, the mixture is filtered and the filtrate stripped ofsolvent. The solid residue is extracted in a Soxhlet apparatus withpetroleum ether to remove impurities, such as unreacted chlorocarbonateintermediate. These solids together with those obtained after removal ofinorganic salts from the original filter cake with water, amount to 9.1parts, or percent of theory, of the carbamate of2-oximino-1,3-dithiolane having a melting point equal to C.-132 C. Afterrecrystallization from a chloroform-hexane mixture, the product melts at133 C.-135 C. and analyzes in percent as follows for C H N O SCalculated: C, 27.1; H. 3.4; N, 15.7; S, 36.0. Found: C, 27.2; H, 3.6;N, 15.9; S, 35.8.

EXAMPLE 20 Preparation of the N-methyl carbamate of 2-0ximino-L3-oxathiolane A mixture of 1.67 par-ts of 2-oximino-1,3-oxathiolane, 0.90part (by volume) of methyl isocyanate, and a trace of triethylamine in10 parts of dry ether is allowed to stand for two days. Evaporation ofthe ether and recrystallization of the residue from anisopropanol-hexane mixture gives 1.43 parts, or 57.8 percent of theory,of the carbamate, having a melting point of 882 C.90.2 C. A secondrecrystallization renders a product melting at 89'.6 C.90.8 C.

Analysis for C H N O S. Calculated: C, 34.07; H, 4.5 8.; N, 15.90; S,18.20. Found: C, 34.40; H, 4.94; N, 16.05; S, 18.37.

EXAMPLE 21 Preparation of the N-methyl carbamate of 4-methyl-2-oximino-1,3-dithi0lane A mixture of 9.1 parts of4-methyl-2-oximino-1,3-dithiolane, 3.7 parts (by volume) of methylisocyanate and 0.3 part of triethylamine in 75 parts of dry ether isstirred and allowed to stand overnight. Evaporation of the ether rendersa crude oil product. The major portion of crude material is purified bymolecular distillation to give 8.6 parts, or =68 percent of theory, ofthe pure product.

Analysis for C H N O S Calculated: C, 34.93; H, 4.89; N, 13.58; S,31.09. Found: C, 34.91; H, 5.18; N, 13.81; S, 30.99.

EXAMPLE 22 Preparation of the N-methyl carbamate 0 Z-oximino-1,3-dithiane To an ice-cooled mixture of 6.0 parts of 2-oximino-1,3-dithiane and 0.2 part of triethylamine in 25 parts of dry ether areadded 2.5 parts (by volume) of methylisocyanate. After coming to roomtemperature, the mixture is refluxed for two hours. Sufficientchloroform is added to dissolve the oil which formed and the mixture iswashed with dilute sodium hydroxide solution and water and dried.Stripping 01f the solvent leaves 6.0 parts or 72 percent of theory ofproduct as an oil which is induced to crystallize and melts at 89 C.-92C. Recrystallization from a benzene-hexane mixture yields short,colorless needles having a melting point of 92.'8 C.-93.8 C.

Analysis for C H N O S Calculated: C, 34.93; H, 4.86; S, 31.09. Found:C, 35.29; H, 5.26; S, 31.08.

EXAMPLE 23 Preparation of the N-methyl carbamate of 4,5-dimethyl-2-oximino-1,3-dithiolane To a stirred ice-cooled mixture of 9.0 parts of4,5- dimethyl-2-oximino-1,3-dithiolane and 0.1 part of triethylamine in25 parts of dry ether are pipetted 3.8 parts by volume ofmethylisocyanate. The ice bath is removed after 30 minutes and themixture allowed to stand overnight. The mixture is recooled by means ofan ice-bath. Thus-formed solids are collected and recrystallized frombenzene-hexane to yield 10.1 parts or 82.1 percent of theory of thecarbamate having a melting point of 74 C.-

. 9 77 C. and analyzing as follows for C H N O S Calculated: C, 38.17;H, 5.49; N, 12.72; S, 29.11. Found: C, 38.25; H, 5.64; N, 12.78; S,29.1%.

EXAMPLE 24 Preparation of the N-methyl carba'mate of 5-methyl-2-ximin0-1,3-0xathi0lane The procedure described in Example 16 is followedin every detail employing -methyl-2-oximino-1,3-oxathiolanehydrochloride instead of 2-oxi'rnino-1,3-dithiolane and chloroforminstead of ether as solvent. The solid N-methyl'carbamate of5-methyl-2-oximino-1,3-oxathiolane melting at 95 C.98 C. is obtained in92 percent yield after recrystallization from benzene-hexane. Resultantcarbamate analyzes as follows:

Calculated for C H N O S. C, 38.09; H, 4.80; N, 14.86; S, 16.95. Found:C, 38.01; H, 5.32; N, 14.80; S, 16.85.

EXAMPLE 25 Preparation of the N-methyl carbwmate of 4-n-butyl-2-oximino-J,3-dithi0lane The procedure described in Example 16 is followedemploying 4-n-butyl-2-oxi-mino-1,3-dithiolane instead of2-oxi'mino-1,3-dithiolane. The N-methylcar-bamate of4-nbutyl-Z-oximino-1,3-dithiolane is obtained in 73 percent yield as asolid melting at 75 C.78 C. after recrystallization from ether-petroleumether. On analysis, the following data is further obtained:

Calculated for C H N O S C, 43.69; H, 6.11; N, 11.33; S, 25.92. Found:C, 43.69; H, 6.06; N, 11.42; S, 26.10.

EXAMPLE 26 Preparation of the N-methyl carbamate of 4-phenyl-2-oximino-Ij-dithiolane The procedure of Example 16. is followed employing4-phenyl-2-0Ximino-1,3-dithiolane instead of 2-oximino- 1,3-dithiolane.The N-methyl carbamate of 4-phenyl-2- oximino-1,3-dithiolane isrecovered in 64 percent yield as a solid melting at 131 C.133 C. afterrecrystallization from methanol-water. The carbamate analyzes asfollows.

Calculated for C11H12N202S2. C, H, N, 10.44; S, 23.89. Found: C, 49.01;H, 5.03; N, 10.30; S, 23.68.

EXAMPLE 27 Preparation of the N-methyl carbamate of 4,4-dimethyl-2-0ximin0-1,3-dithi0lane The procedure of Example 16 is repeated inevery detail, except that 4,4-dimethyl-2-oximino-1,3-dithiolane isemployed instead of 2-oximino-1,3-dithiolane. The crude solid carbamateis employed directly for insecticidal testing. It is characterized byits infrared absorption spectrum which shows an NH band at 3300 cmf aC=O band at 1720 cm.- a C=N band at 1540 cmf and an NO band at 940CIR-1.

To illustrate the insecticidal activity of the carbamates of2-oximino-1,3-dithiolanes, 1,3-oxathiolanes, 1,34iithianes and1,3-oxathianes of the present invention, the following example ispresented:

EXAMPLE 28 Representative compounds illustrated by structure in thetable below are diluted with a mixture of 65-35 acetone-water,respectively, to produce the several tabulated concentrations. Potscontaining two or three Nasturtium plants two inches tall are infestedwith Nasturtium aphids two days before they are selected for testing.The pots are placed on a turntable and the plants are sprayed with atest compound. It is observed that the percent kill of the aphids foreach concentration given in the table below is high. Typical values areshown.

TABLE I Percent Kill Aphids Concentration Compound (Ha-S O C=NO lNHCHa100 100 100 CHg-S (Hz-S C=N-O lNHCzHs 100 100 CH2S (Hg-S C=NO N (CH3);100 100 100 CHPS O C=NO lNHa 100 100 100 CH2'S CH;S I

C=N-O lNHcHa 100 100 100 CHr-S C=N-O l lNHCHa 100 100 100 C 3CHzS CH2S 0H O O=N O C lNHCHa 100 100 95 CH2S CH2S O C=NO jlNH CH3 100 100 100 CHCHO Q0 H-S o II I C=NOONHCH3 0 CH2S C 4H C H-S O O=N O lNHCHa 100 100CH2S CHa-OH-S O C=NO /NH CH: 100 100 CHaCH-S C- S I C =N-O ('lNHCHa 100100 100 C 3 It is an advantage to utilize the insecticidal compositionsof the present invention in dilute concentrations by incorporating thelatter compounds in a variety of inert carriers or diluents. Forinstance, the compounds may be dissolved in an inert organic solventsuch as acetone, ethyl acetate, ethyl alcohol, benzene, kerosene andequivalents thereof, or they may be admixed with an inert solid carrieras, for example, fullers earth, bentonite, and the like. If desired, asuspension of the active compounds may be prepared by employing anon-solvent. In that event, it is advantageous to add thereto anycommercially available dispersing -or surface-active agent of theanionic or nonionic types.

Although the compounds of the present invention have been illustrated aspossessing activity against aphids, they can also be advantageouslyemployed in dilute concentrations as excellent miticides.

The quantity of inert solid or liquid carrier or diluent with respect toinsecticidal compounds is not critical. It has, however, been found thatfrom about 0.000l% to about by weight of the compound, based on theweight of the inert carrier is generally sufiicient.

What is claimed is:

1. A composition comprising a major proportion of an inert insecticidalcarrier and a minor amount of a carbamate of the formula:

a, BK n R R R and R are each selected from the group consisting ofhydrogen, lower alkyl and phenyl, Q represents an atom selected from thegroup consisting of oxygen and sulfur, n is an integer from 0 to l, andR and R are each a radical selected from the group consisting ofhydrogen and lower alkyl.

2. The composition according to claim 1 in which the carbamate is thecarbamate of 2-oximino-l,3-dithiolane.

3. The composition according to claim 1 in which the carbamate is theN-methyl carbamate compound of 2- oximino-1,3-dithiolane.

4. The composition according to claim 1 in which the carbamate is theN-1nethyl carbamate compound of 2- oXimino-l,3-oXathiolane.

5. The composition according to claim 1 in which the carbamate is theN-methyl carbamate compound of 2- 0Ximino-4-methyl-1,3-dithiolane.

6. The composition according to claim 1 in which the carbamate is theN-methyl carbamate compound of 2- oxi minol ,3-dithiane.

7. A process adapted for the control of insects which comprises applyingto said insects a mixture comprising a major amount of an inert carrierand a minor amount of a carbamate defined in claim 1, said carbamatebeing present from about 0.0001% to about 10% by weight, based on theweight of the inert carrier.

8. The method according to claim 7 in which the carbamate compound isthe carbamate of 2-oximino-l,3 dithiolane.

9. The method according to claim 7 in which the carbamate compound isthe N-methyl carbamate compound of 2-oximino-1,3-dithiolane.

10. The method according to claim 7 in which the carbamate compound isthe N-methyl carbamate compound of 2oximino-1,3-oxathiolane.

11. The method according to claim 7 in which the carbamate compound isthe N-methyl carbamate compound of 2-oximino-4-methyl-1,3-dithiolane.

12. The method according to claim 7 in which the carbamate compound isthe N-met-hyl carbamate compound of 2-oximino-1,3-dithiane.

References Cited UNITED STATES PATENTS 3,183,148 5/1965 Cannon et al.167-33 ALBERT T. MEYERS, Primary Examiner.

FRANK CACCIAPAGLLA, IR., JULIAN S. LEVITT,

' Examiners. J. D. GOLDBERG, Assistant Examiner.

1. A COMPOSITION COMPRISING A MAJOR PROPORTION OF AN INERT INSECTICIDALCARRIER AND A MINOR AMOUNT OF A CARBAMATE OF THE FORMULA: